The present invention relates to a process to prepare metastasis-inhibitory factor (abbreviated as "MIF" hereinafter), in particular, to a process to prepare MIF which comprises allowing an established human hematopoietic cell to produce MIF, and recovering the MIF. 2. Prior art
The expectation of life at birth in Japan is increasing year by year. According to Nippon Tokei Nenkan (Japanese Statistical Yearbook), 37th edition, published by the Japan Statistical Association (1987), the expectation of life at birth in 1985 was 74.78 years for male and 80.48 years for female. The most predominant cause of death is malignant neoplasms or cancers which account for about 25% of the total death.
Treatment of cancers has been carried out predominantly with surgical operation, chemotherapy and irradiation. These therapies, however, can kill a major part of a growing cancer, but may disperse the remaining vial cancer cells in patient's body to accelerate its metastasis. This may result in a much more serious metastasizing cancer and shorten much more the remainder of patient's life.
If the metastasis of cancer is prevented, then the patients' pain is relieved and the remainder of their life may be remarkably prolonged. Thus, the development of any method which effectively suppresses the metastasis of cancers has been in great demand.